Figure 7. Inheritance mechanism for post-mitotic NPC assembly.

Cartoon summarizes a mechanism that explains the post mitotic formation of nuclear pore complexes. It represents the assembly of nuclear pore complexes during two sequential cycles of cell division and highlights the mechanistic differences between post-mitotic and interphase incorporation to nuclear pore complexes of inner and outer ring components. The representation does not show the location of the inner and outer-ring octameric templates that remain intact in the mitotic ER after NPC disassembly during prophase. The precise locations of the octameric outer and inner ring templates within the mature NPC remain to be determined. Even after ~10 cell divisions, progeny cells contain intact outer and inner ring nuclear pore subassemblies inherited from their great-great-great-great-great-great-great-great grandmothers. These effectively “immortal” subassemblies then template post-mitotic NPC formation, largely in regions of the nascent nuclear envelope (“non-core” regions) displaced from the residual mitotic spindle. In this inheritance mechanism, each nuclear pore in the mother cell produces the templates for one nuclear pore in one of the two daughter cells; the same template is re-used during subsequent cell divisions.